In general, a dual mass flywheel includes a primary mass and a secondary mass which are relatively rotatable within a limited range and an elastic member for damping the torsional vibrations by being installed between the primary and secondary masses while transmitting a rotational force.
Such dual mass flywheels play a role of damping the torsional vibrations which occur when transmitting torque. The vibrations are caused by a sudden increase or decrease in the number of revolutions of the engine—from the engine to the transmission.
The primary mass engages an output element (for example, the crank shaft) of the engine and the secondary mass engages an input element of the transmission. The secondary mass and an input side of the transmission are engaged and disengaged through a clutch. In general, the primary mass and the secondary mass are connected by means of a spring.
However, it is difficult to obtain optimal damping characteristics using current dual mass flywheels, where the optimal characteristics are based on the torque characteristics for each number of revolutions.